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961.
962.
Marcelo Soto Laura Sampietro-Colom Anna Vilella Efraín Pantoja María Asenjo Ruth Arjona Juan Carlos Hurtado Antoni Trilla Míriam José Alvarez-Martínez Aurea Mira Jordi Vila María Angeles Marcos 《PloS one》2016,11(1)
Seasonal influenza causes significant morbidity and mortality and has a substantial economic impact on the healthcare system. The main objective of this study was to compare the cost per patient for a rapid commercial PCR assay (Xpert® Flu) with an in-house real-time PCR test for detecting influenza virus. Community patients with influenza like-illness attending the Emergency Department (ED) as well as hospitalized patients in the Hospital Clínic of Barcelona were included. Costs were evaluated from the perspective of the hospital considering the use of resources directly related to influenza testing and treatment. For the purpose of this study, 366 and 691 patients were tested in 2013 and 2014, respectively. The Xpert® Flu test reduced the mean waiting time for patients in the ED by 9.1 hours and decreased the mean isolation time of hospitalized patients by 23.7 hours. This was associated with a 103€ (or about $113) reduction in the cost per patient tested in the ED and 64€ ($70) per hospitalized patient. Sensitivity analyses showed that Xpert® Flu is likely to be cost-saving in hospitals with different contexts and prices. 相似文献
963.
964.
Román Serrat Guillermo López-Doménech Serena Mirra Martí Quevedo Jordi Garcia-Fernàndez Fausto Ulloa Ferrán Burgaya Eduardo Soriano 《PloS one》2013,8(7)
The regulation of mitochondrial dynamics is vital in complex cell types, such as neurons, that transport and localize mitochondria in high energy-demanding cell domains. The Armcx3 gene encodes a mitochondrial-targeted protein (Alex3) that contains several arm-like domains. In a previous study we showed that Alex3 protein regulates mitochondrial aggregation and trafficking. Here we studied the contribution of Wnt proteins to the mitochondrial aggregation and dynamics regulated by Alex3. Overexpression of Alex3 in HEK293 cells caused a marked aggregation of mitochondria, which was attenuated by treatment with several Wnts. We also found that this decrease was caused by Alex3 degradation induced by Wnts. While the Wnt canonical pathway did not alter the pattern of mitochondrial aggregation induced by Alex3, we observed that the Wnt/PKC non-canonical pathway regulated both mitochondrial aggregation and Alex3 protein levels, thereby rendering a mitochondrial phenotype and distribution similar to control patterns. Our data suggest that the Wnt pathway regulates mitochondrial distribution and dynamics through Alex3 protein degradation. 相似文献
965.
Increasing drought decreases phosphorus availability in an evergreen Mediterranean forest 总被引:9,自引:2,他引:7
Mediterranean ecosystems are water-limited and frequently also nutrient-limited. We aimed to investigate the effects of increasing
drought, as predicted by GCM and eco-physiological models for the next decades, on the P cycle and P plant availability in
a Mediterranean forest. We conducted a field experiment in a mature evergreen oak forest, establishing four drought-treatment
plots and four control plots (150 m2 each). After three years, the runoff and rainfall exclusion reduced an overall 22% the soil moisture, and the runoff exclusion
alone reduced it 10%. The reduction of 22% in soil moisture produced a decrease of 40% of the accumulated aboveground plant
P content, above all because there was a smaller increase in aerial biomass. The plant leaf P content increased by 100 ± 40
mg m−2 in the control plots, whereas it decreased by 40 ± 40 mg m−2 in the drought plots. The soil Po-NaHCO3 (organic labile-P fraction) increased by 25% in consonance with the increase in litterfall, while the inorganic labile-P
fraction decreased in relation to the organic labile-P fraction up to 48%, indicating a decrease in microbial activity. Thus,
after just three years of slight drought, a clear trend towards an accumulation of P in the soil and towards a decrease of
P in the stand biomass was observed. The P accumulation in the soil in the drought plots was mainly in forms that were not
directly available to plants. These indirect effects of drought including the decrease in plant P availability, may become
a serious constraint for plant growth and therefore may have a serious effect on ecosystem performance. 相似文献
966.
Jose Luis Araus Shawn Carlisle Kefauver Omar Vergara‐Díaz Adrian Gracia‐Romero Fatima Zahra Rezzouk Joel Segarra Maria Luisa Buchaillot Melissa Chang‐Espino Thomas Vatter Rut Sanchez‐Bragado José Armando Fernandez‐Gallego Maria Dolores Serret Jordi Bort 《植物学报(英文版)》2022,64(2):592-618
High-throughput crop phenotyping, particularly under field conditions, is nowadays perceived as a key factor limiting crop genetic advance. Phenotyping not only facilitates conventional breeding, but it is necessary to fully exploit the capabilities of molecular breeding, and it can be exploited to predict breeding targets for the years ahead at the regional level through more advanced simulation models and decision support systems. In terms of phenotyping, it is necessary to determined which selection traits are relevant in each situation, and which phenotyping tools/methods are available to assess such traits. Remote sensing methodologies are currently the most popular approaches, even when lab-based analyses are still relevant in many circumstances. On top of that, data processing and automation, together with machine learning/deep learning are contributing to the wide range of applications for phenotyping. This review addresses spectral and red–green–blue sensing as the most popular remote sensing approaches, alongside stable isotope composition as an example of a lab-based tool, and root phenotyping, which represents one of the frontiers for field phenotyping. Further, we consider the two most promising forms of aerial platforms (unmanned aerial vehicle and satellites) and some of the emerging data-processing techniques. The review includes three Boxes that examine specific case studies. 相似文献
967.
968.
969.
Xavier Arnan Anna Escolà Anselm Rodrigo Jordi Bosch 《Botanical journal of the Linnean Society. Linnean Society of London》2014,175(3):395-408
Gynodioecy is a dimorphic breeding system in which female individuals coexist with hermaphroditic individuals in the same population. Females only contribute to the next generation via ovules, and many studies have shown that they are usually less attractive than hermaphrodites to pollinators. Several mechanisms have been proposed to explain how females manage to persist in populations despite these disadvantages. The ‘resource reallocation hypothesis’ (RRH) states that females channel resources not invested in pollen production and floral advertisement towards the production of more and/or larger seeds. We investigated pollination patterns and tested the RRH in a population of Thymus vulgaris. We measured flower display, flower size, nectar production, visitation rates, pollinator constancy and flower lifespan in the two morphs. In addition, we measured experimentally the effects of pollen and resource addition on female reproductive success (fruit set, seed set, seed weight) of the two morphs. Despite lower investment in floral advertisement, female individuals were no less attractive to pollinators than hermaphrodites on a per flower basis. Other measures of pollinator behaviour (number of flowers visited per plant, morph preference and morph constancy) also showed that pollinators did not discriminate against female flowers. In addition, stigma receptivity was longer in female flowers. Accordingly, and contrary to most studies on gynodioecious species, reproductive success of females was not pollen limited. Instead, seed production was pollen limited in hermaphrodites, suggesting low levels of cross‐pollination in hermaphrodites. Seed production was resource limited in hermaphrodites, but not in females, thus providing support for the RRH. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 175 , 395–408. 相似文献
970.
Karen B. Disante Jordi Cortina Alberto Vilagrosa David Fuentes Encarni I. Hernández Karin Ljung 《Physiologia plantarum》2014,150(3):412-424
Heavy metal contamination and drought are expected to increase in large areas worldwide. However, their combined effect on plant performance has been scantly analyzed. This study examines the effect of Zn supply at different water availabilities on morpho‐physiological traits of Quercus suber L. in order to analyze the combined effects of both stresses. Seedlings were treated with four levels of zinc from 3 to 150 µM and exposed to low watering (LW) or high watering (HW) frequency in hydroponic culture, using a growth chamber. Under both watering regimes, Zn concentration in leaves and roots increased with Zn increment in nutrient solution. Nevertheless, at the highest Zn doses, Zn tissue concentrations were almost twice in HW than in LW seedlings. Functional traits as leaf photosynthetic rate and root hydraulic conductivity, and morphological traits as root length and root biomass decreased significantly in response to Zn supply. Auxin levels increased with Zn concentrations, suggesting the involvement of this phytohormone in the seedling response to this element. LW seedlings exposed to 150 µM Zn showed higher root length and root biomass than HW seedlings exposed to the same Zn dose. Our results suggest that low water availability could mitigate Zn toxicity by limiting internal accumulation. Morphological traits involved in the response to both stresses probably contributed to this response. 相似文献